Derrick



UNITED STATES PATENT OFFICE.

JOHN B. HOLMES, OF BOSTON, MASSACHUSETTS.

DERRICK.

specincation of Letters Patent No. 10,544, dated February 21, 1854.

side of a boom derrick. Fig. 2 is an endf elevation of the same. Fig. 3 is a top View thereof. Fig. 4, is a View of certain parts ofk the winch barrels and take up apparatus on a large scale. Fig. 5 is a section lengthwise f through one of the takeup drums showing'4 the friction connection thereof with its shaft and the friction band or strap applied thereto. Fig. 6 is a side elevation of a boom f derrick somewhat different in Yarrangement v from the others, and Fig. 7, is a topview of the derrick represented in Fig. 6.y

The nature of the first part of .my invention, consists in arranging the, platform which carries the winches or their equiva-y lents'in such manner that it is supported by a `collar upon which it may revolve, is also held down to said collar by clamps or their equivalents and is further in connection with the revolving cap which carries the mast head blocks by means of tension braces or' their equivalents, whereby I am enabled to use a very light mast and dispense with the guys from the head thereof to anchors etc. And the nature of the second part of my invention consists in .attaching the heel lof the boom ata point upon the platform vbetween the mast and the winch or on'that side of the mast or center of theh platform which is most distant fromrthe weight be! rfrom smallerwheelsattached to the shafts ing moved. In derricks for lifting heavy weights this boom is of necessity strong and consequently heavy, land the position of its center of gravity exercises an important influence on the stability of the whole apparatus. By my arrangement the center of gravity of this boom` is thrown farther fromV the weight and nearer to the center of the whole apparatus whose stability is consequently materially increased.

In Figs. 1, 2v and 3 of the drawings (a) represents the mast of the derrick in this instance sustained in a Vvertical position by chains attached to bolts secured in a platform or to the top of a tower or other struc-l revolving platform which carries the ture in process of construction, (b) is the Winches, drums, etc., as also the heel ofthe boom (g) which is vin, this instance forked so a(s )to embrace the mast, and is supported at 7: j. i

' The revolving cap (c) is supported on the spindle shown in dotted lines in Fig. "1 only and isv firmly attached by tensiony braces (d al) tothe revolving platform. This latter rests (as clearly shown by the sectional portion of Fig. 1) on a collar (e) friction rollers being interposed and is confined down upon said collar by clamps (f f) or their equivalents, which are also provided with friction rollers. By means of' this arrangement it will be perceived 'that ythe strain tending to'bend or break the mast is counteracted by the rods which in their turnv are prevented from rising through their connection Vwith the platform,which y cannot lift until it breaks-the clamps or the v collar. i

Ijn thewinches exhibited in these drawings the `ordinary surgingV barrel is employed;V two barrels on each shaft, one for each end .ofia fall. vThe barrels nearest the mast being those which govern the fall for raising 'and lowering ythe end of the boom, andthe drums farthest from the mastv being those which' control the ends of the fall for raising yand lowering the weight.` vThese drums are lietteredl (j j, ,7c le) and their connection with YtheV L,mast head leading blocks with .the sheaves in the end of the boom and Withithev running block Awhich carries the weight, is so'. V clearly shown in the drawings `that further description thereof is deemed unnecessary.` Each drum shaftv is provided with a toothed l-wheel (l, m) which receives motion on which are mounted the cranks (n, o)

Each'se't of `drums is alsorprovided with appropriate ratchets, ratchet wheels, etc.and

between them is appropriately` supported" a small shaft (p) on which is mounted`` the wheel (g). This shaft'can be moved co enwise atwilland its wheel. thereby enitin toward the `center ofthe derrick, the 1 small shaft (79) is moved in the direction of the arrows and its cog (g) engages with both Z and m as in Fig. 4;. One of the ratchets is now thrown out of gear and one of the cranks (n) is turned in the direction indicated by the arrow Fig. 4. Mot-ion is therefore. communicated to all the barrels and shafts as shown by arrows in Fig. 4,

and while the drum winds up bo-th ends i with this method of connect-ing the operation of the boom end purchase with that which operates on the weight, two gangs of hands one tending each winch must be employed to give' these motions in a hori- Zontal direct-ion to the suspended weight,

and each gang must be of sufficient force to control or raise the weight, whereas by my plan only one gang is needed, and that one may be comparatively weak, as it needs only to control such proportion of' the Vwhole weight as is due to the short distance it rises or falls when compared with the distance it moves in a horizontal direction. It is obvious further that the power maybe applied to the vother winch in theproper direction and that the same effect will follow.

At (u, fu, u) Figs. l, 2 and 3 is exhibited a crank attached to a vertical shaft mounted on the revolving platform and provided with a small cog which engages with the large cog (fw Fig.2) securedto the collar (e). By turning the handle the platform can be revolved` in either direction.

Below each set of drums Figs. l, 2, 3 and t are arranged `take up drums (j, 7%)

which receive motion through gearing driven by the winch shafts, see cog wheels (w, fm', Z) in some instances represented merely by a circle. may be driven by any other appropriate gearing or mechanical devices for conveying rotary motion, and are driven at vsuch speed that any `point on their periphery may be moved at least as fast as any point' on the peripheries of the main drums to which they are secondaries. The ends of the falls after taking one or more turns around the main drums are led to the secondary orV take up drums and rmly attached to their peripheries. It is evident however that when therope had been woundup so as to cover the whole surface of the secondary drum, andV commenced to envelop it withV a second layer, that it would Vthen be wound upon a cylinder whose effective diameter would be the original size of the drum The l These` take up drums Y 'cease' or the fall must part between the main and secondary drums. In order to remedy this defect I have so constructed the latter drumsthat they may be free to slip on their shafts andthus accommodate themselves t0 Vthe precise amount of motion required no matter how many layers of rope are wound upon them.

By reference to Fig." 5 my method of` thus attaching the drum to its shaft will be clearly perceived. The secondary drum shaft (A A) receives mot-ion from any other shaft connected with `the main drum shaft or directly from the latter shaft, and upon it is firmly keyed a disk or rather short cyl-` inder (B'B) bored'o-ut conically (at C C) and if necessary lined with'leather or wood.

'Ihe take up drum proper (D D) is free to turn on the shaft and upon the periphery of a nut (E E) which may by means of a wrench be caused to traverse along a screw (F) and thereby compress or permit to eX- pand a spiral spring (G) one end ofwhich abuts against the nut, while `the other end rests against an interior flange (I-I) or may be extended and abut directly against the drum head (H). This drum head is turned off conically on its outer periphery and fits closelyV with the partC' C of the desk B, being pressed with some force into the cavity by `means of the spiral spring whose tension is regulated by the nut (E). It is evident that the Vwhole arrangementforms a species of friction` coupling and that the drum will revolve as fast as its shaft unless the former 'y be retarded by a force suiiicient to overcome the frictionof the two parts of the conical coupling." Vhen thisforce comes into operation, this Vdrum will slip von its shaft; and it comes into effect :when the fall commences to envelop the take up drum proper with its second layer of rope; when if the friction be less than can be overcome by the strength of the rope) the said take up drum will slip, its` periphery will `be retarded and it will in consequence take up the fall just as fast vas it is delivered to it by its'primary drum.

If but one layer of rope be `wound upon the take up drum while hoisting, it is obvious that said rope will be delivered precisely at the proper rate while lowering;

but if more than one layer of rope be wound upon the take up drum, thenwill the said 'drum when the lowering is commenced deliver the fall at too great a rate of speed to 4its primary or main drum. The fall would therefore surge around the Vmain drum, letting the weight fall too fast by a seriesof jerks and endangering ythe whole apparatus. if

To remedy this inconvenience I haveprovided each take up drum with la frlction the take up drum to move slower than its shaft during the operation of lowering, slipping` according to the judgment of the brakesman to just such a degree, as is necessary to deliver the fall to the main drum at the proper speed. The friction band is provided with an actuating lever, and may be used in case of accident from breakage, to hold the weight in any position to which it may have arrived. It is hardly necessary to state that such a brake is in practice a`pplied to each take up drum. One of these brakes is clearly represented at letter R, in Fig. 5, with its handle S, and two of these brakes in their proper position are represented at (R R) Fig. l.

In Figs. 6 and 7 I have exhibited a crane or derrick in which are embodied` all the points of my invention save one under a somewhat different form and arrangement. Instead of the mast I there employ a strong framing (a o) firmly held together by diagonal bracing on a platform attached to'which is secured a revolving cap {0) The boom (g) is pivoted on that side of the platform most distant from the weight, and the latter surrounds the whole frame and traverses on friction rollers mounted on a collar (e) shown in Fig. 6 Where the platform is shown as partially broken away. This platform (b) is connected by braces (d d) `provided with appropriate screw buckles, to the revolving cap.. The Winches, winch drums, gearing, etc., are all mounted in their appropriate place, but instead of the ordinary single surging drum, I have here exhibited as applied to a derrick my double barreled capstan or winch which was secured to me by Letters Patent in June 1841. I have also exhibited purchase blocks, containing a greater number of sheaves, and have so arranged the tackles that I hoist from one end of the falls only. The clamps (f, f, f,) for securing the platform underneath the collar are exhibited in Fig. 6 only, and the apparatus for revolving the platform lseen, at (w o u) is arranged with a hand wheel and bevel gearing, and is also provided with a pulley (a) which may be driven by a belt from a pulley onthe crank shaft (yr) the crank of which (g/) is fitted to be driven by a small engine located on the red cent-er line Fig. 7. This engine if used kwill drive the whole machinery, proper gearing being exhibited on the drawing Vand its boiler may be located as shown upon the drawing. l f

Many methods of making a friction connectionr between a drum and its shaft are now in use and well known to mechanics,

and it is evident that any such device may Y be employed in lieu of those shown by me without altering the character of my invention and further that any known method of communicating rotary motion, may be employed for making the connection between the main drums and the take up drums.

Having thus clearly described my invenl tion and the apparatus for carrying it int-o effect, I claim as of my own invention and desire to secure by Letters /Patent of the United States.

1. The combined arrangement of the-co lar upon the mast; the revolving platform supported upon it and clamped below it, and the tension rods from said platform to the revolving-mast-head-cap in the manner and for the purposes described.

2. Pivoting theheel of the derrick-boom upon lthe revolving platform in the locality substantially such as is herein represented and described, that is upon that portion of the platform which is beyond the, center of the platform when measuring from theV point of suspension of thev weight.

In witness whereof I have hereto set my hand in the presence of two subscribing witnesses this 17th day of February1853.

JOHN B. HoLMHs.

Witnesses:

D. D. WINANT, PHILIP MrLsrAUGH. 

